It is not necessary to concur with Singer’s
position of drawing no line whatever between the moral status of
humans and other species in order to welcome Dawkins’s carefully
considered suggestions for devising behavioural measurements of
preference, on the assumption that these could be helpful in
minimizing the non-preferred emotional states experienced by
captive animals. While I argued for certain kinds of continuity in
the psychological processes of humans and other species in the
book referred to by Dawkins, there remains ample evidence for
significant discontinuities, which undercut the assumption that
there is a simple dimension of suffering which can be put into
cross-species utilitarian equations of the kind Singer appears to
propose. For instance the traditional marker of language as a
special determinant of human cognition has resisted all efforts to
blur it (Premack, 1987, Chomsky, 1980). The equally venerable view
that distinctive of aspects of human mentality are culturally
determined (and/or “socially constructed”) is still vigorously
promoted (e.g. Harre, 1986).

Therefore, while scientists should be (and are legally)
obliged to accept the commonsense view that animals can suffer,
Singer’s argument (precommentary, p.5) that we should consider
human and non-human suffering as essentially similar to our own
defends, as he points out, a much stronger position. It is worth
noting that the commonsense view seems to recognize differences in
the moral status of animals - many pet owners neuter their charges
when they are young and vigorous, and “put them down” when they
are old and feeble. Philosophical and empirical analyses may be
able to support this distinction: it might be claimed that fear of
being castrated, or (resentment at having been so treated) is both
socially constructed and linguistically mediated; or following
Dawkins it might be possible to show that fear of going to the
vets’ (or of a standard signalling stimulus) is no greater for
animals after a painless neutering experience that after a control
condition involving no loss of natural function.

Dawkins’ article is both moderate and practical, and under
“Problems with this approach” she seems to have considered most of
the difficulties that could arise from too stringent an
application of her main recommendation of assessing preference
according to the principle of “inelastic demand”. In now
emphasising some of the problems I do not wish to detract from the
advantages of her behavioural approach.

A theoretical problem which may be minor in practice is that
inelasticity may indicate automaticity of behaviour rather than
high emotional value in some species, or in special cases. Suppose
for instance that a cockroach (Horridge, 1962) or a decerebrate
embryo (Heaton et al, 1981) showed inelasticity of response
effort in avoiding aversive stimuli, or that a decorticate mammal
showed less sensitivity than normal to response cost in food
rewarded behaviour (e.g. Oakley, 1979). Should we assume greater
suffering, or the operation of a more mechanical motivational
system? A greater difficulty is that high elasticity of demand
might conversely indicate more cognitive representations of goals
or “declarative” emotional states (McFarland, 1989). Pigs might
show elastic demand for social companions by comparison with food
(p.11 target article) because of a relatively blind drive for
food, and a more considered evaluation of the social benefits used
in a particular experiment. For practical purposes this sort of
potential problem is covered by Dawkins’ solution of using several
measures of welfare (e.g. of the general condition of socially
isolated though well fed pigs), but a greater distinction may need
to be made between intensity of motivational effects on behaviour
and the type of cognitive representation involved in a given
motivational effect (Dickinson, 1985, Walker, 1987)

A more global reservation which applies both to parts of the
target article and to the precommentary concerns the relation
between suffering and natural behaviours. Dawkins’ conclusion is
that it is an empirical question whether the absence of the
opportunity to perform a natural activity such as migration leads
to suffering, but she tends to assume that it is only the
prevention of motivated acts, and not the natural performance of
such acts, that could be associated with unpleasant emotional
states. On the other hand Singer seems to suggest that we have a
duty to reduce pain and suffering that may arise in animals’
natural conditions (p.5). There is surely something to be said for
the point that natural life itself may involve high levels of
stress - for instance during migration, hard winters for non-
migrators, disease, drought and famine for all and predation for
prey. Thus while supporting Dawkins’ idea that negative
motivational states due to the prevention of natural behaviours in
captive animals should be empirically assessed, and steps taken to
minimize them, I am not convinced of the implied corollary that
animals free to engage in natural behaviours always suffer less.
Since the main issue is the care of captive animals this is not
directly relevant, but it would have serious implications if one
accepted Singer’s position that the welfare of wild animals (in
the case, for example, of infant mortality rates) is as deserving
of concern as is that of our own species.